Typewriter chair



Sept. 9, 1930. KRABQL 1,775,433

TYPEWRITER CHAIR Filed Nov. 6, 1928 O/aws O. JCnQboL 39 M WMQW PatentedSept. 9, 1930 UNITE-D STATES PATENT OFFICE OLAUS O. KRABOL, OF CHICAGO,ILLINOIS, ASSIGNOR TO COLONIAL" CHAIR COMPANY,

' A CORPORATION OF ILLINOIS TYPE'WRITER CHAIR Application filed November6, 1928. Serial No. 317,500.

This invention relates to seats or chairs, and more particularly tobacks for typewriter chairs and the like.

The principal object of the invention is the provision of new andimproved means for supporting back rests on the back standards oftypewriter chairs in such a manner that they may automatically adjustthemselves to the back of the typist.

Another object of theinvention is the provision of a new and improvedhinge mechanism for mounting the back rests of typewriter chairs so thatsaid rests may auto-' matically adjust themselves in use and beyieldingly held in operative position at all times. I

A still further object of the invention is the provision of a new anduseful back rest supporting member or mounting that is simpleinconstruction, cheap to manufacture, easily assembled, efficient inoperation, and will be automatically adjusted to the most comfortableposition for the occupant when in use.

Other and further objects and advantages will appear fromthe followingdescription takenin connection with the accompanying drawings, in whichFig. 1 is a side elevation of a typewriter chair, showing the inventionin position thereon;

Fig. 2 is a vertical section through the back member and back rest,showing the inven; tion in position therein, with parts broken away;

Fig. 3 is a vertical section on the broken line shown in Fig. 2 andlooking in the direction of thearrows 33; and

' Fig. 4 is a similar section but looking in the direction of the arrows4-4 in Fig. 2. 8

On the drawings, the reference character 10 designates generally atypewriter chair comprising the seat portion 11, supporting pedestal 12and back member 13. The back member may be adjusted vertically and heldin adjusted position by the clamping member 14, and be adjustedangularly by the adjusting mechanism 15. The back rest is shown at 16.

well known in the art, it is not thought necessary to further illustrateor describe the same.

It is desirablethat the back rest 16 be so supported that it willreadily and automatically adjust itself to a position While in use thatwill be the most comfortable and at the same time will beyieldingly heldin a predetermined position when not in use. This is accomplished by themechanism that will now be described.

In the form of construction selected to illustrate one embodiment of theinvention, the connection between the back member and rest comprises thehinge member'17 secured to the back member 13 and the hinged member 18secured to the back rest 16. The hinge member 17 may be in the form of aplate provided with hinge ears or lugs 19 and 20 ex tending outwardlytherefrom and having alined openings for receiving a hinge pintle 21,see Fig. 3.- The hinged plate member 18 is provided with ears or hingelugs 22 and 23 which are provided with alined openings for receiving thehinge 'pintle 21, see Figs. 3 and 4, for connecting the plate members17and 18 together. I

Suitable means are provided for normally yieldingly holding said hingedmember 18 in a predetermined position relative to said' hinge member 17.In the form of construction shown, resilient members as the coil springs32 and 33 are employed for this purpose, one above and one below thehinge pintle. In order to increase the resiliency and movement of thesesprings, provision is made for increasingtheir length. One of themembers of Jthe'hinge, as shown, the hinge member 17, is provided withacouple of holes 24 and 25 which are adapted to alinewith openings orrecesses 26 and 27 in the back member 13 as clearly shown in Fig. 2 ofthe drawing. The hinge member 17 is attached studs 29 and 31which areadapted to be in axial alinement with the openings 24 and Since theabove described construction, is

will be received in said openings during ab normal rocking of the backrest 16. Springs 32 and 33 have their rear ends secured in the openingsor recesses 26 and 27 respectively, and engage the studs 29 and 31 forpositioning their forward ends as clearly shown in Fig. 2 of thedrawings, whereby the back rest member 16 will be,yieldingly held in apredetermined position when the chair is not occupied. The hinge andspring members will enable the back rest to beautomatically adjusted toa position most comfortable for the occupant of the chair.

The hinge members 17 and 18 may be formed in any suitable manner.Preferably they are stamped from sheet metal with the ears or pivot lugsextending at right angles to the body of the plate, as clearly shown inFigs. 3 and 4:.

While the hinge device is disclosed as being employed for pivotallysecuring a back rest to a seat back, it is understood that this is byway of example only, and that this device may be used in other relationsor between any hinge and hinged members Where,

it is desirable that the hinged member be normally yieldingly held in apredetermined position.

It is thought from the foregoing taken in connection with theaccompanying drawings that the construction and operation of my devicewill be apparent to those skilled in the art, and that various changesin size,

shape, proportion and details of construction may be made withoutdeparting from the spirit and scope of the appended claim.

I claim as my invention:'

In combination, a seat back member having a pair of openings therein, aback rest member in front of said seat back member, means for connectingsaid members together, said means comprising a hinge plate secured tosaid seat back member and having a pair of openings in alignment withsaid first named pair of openings, a hinge plate attached to said backrest member and pivoted to said first named hinge member between theopenings therein, said last named plate having a pair of rearwardlyextending pins opposite said openings and normally spaced therefrom andadapted to be received therein during abnormal rocking of said back restmember, and a pair of springs, each having a plurality of coilsextending within said openings and encircling said pins for normallyresisting the rocking movement of said back rest member, the openings insaid back memher being of considerable depth whereby comparatively longsprings may be employed without increasing the space between saidmembers.

In testimony whereof I afiix my signature.

OLAUS O. KRABOL.

